1. Field of the Invention
The present invention relates to antenna technology, and more particularly, to an antenna module and an antenna thereof.
2. Description of the Related Art
With the increase of additional functions in handheld communication devices (such as, smart phone, digital camera, tablet computer and PDA, etc.), circuit modules corresponding to these additional functions are compressed into a small size that can be placed in a predetermined configuration space (the inside of a handheld communication device). Thus, miniaturization has become the important developing of circuit modules.
Following the aforesaid trend toward miniaturization in circuit module technology, antenna modules for handheld communication products must be small-sized. To reduce the size of an antenna module, it is normally to limit the configuration space of the antenna module at first, and then to design the antenna size and the antenna drive circuit subject to the limited configuration space. However, whether the drive circuit can be narrowed or not depends on the allocation of the integrated circuit and the related components. However, this point is not the technical content to be improved in the present invention, and it will not be discussed here.
Inverted-L antennas and inverted-F antennas are widely used at the present time. U.S. Pat. No. 6,853,335 disclosed an inverted-L antenna. U.S. Pat. No. 7,443,357 disclosed an inverted-F antenna. The signal feed in direction in the inverted-F antenna of US20120044111 is kept in parallel to the ground element. This is the commonly adopted technique. However, this conventional arrangement does not allow the dimension of the ground element to be significantly reduced. Reducing the dimension will cause the ground element to lose its inductance characteristic, leading to antenna operation failure at the operating frequency. Therefore, when an antenna works at the operating frequency of 2.4G, the antenna configuration
If the operating frequency is set at 2.4G, the size of an inverted-F antenna configured subject to conventional technique will be constrained by the limit of the overall size of the ground element and main radiation element.
Further, because the radiating elements have the same line width, a magnetic flux leakage can occur at every turning corner of each radiating element, affecting the performance of the antenna.
Further, a conventional antenna module generally provides an electrical connector for connection with the ground plane of the main board of a handheld communication product. However, the pins of the electrical connector have a specific length and cannot be shortened. Thus, during a high-frequency application, the pins can induce an extra inductance effect, causing the impedance of the antenna unable to obtain optimal impedance matching.